Maecelltjs l



M. L. CLARKSON.

PLUMB BOB.

Patented De0.-30, 1884.

INVENTOR. 1

677/ 7) ATTORNEYS.

(No Model.)

WITNESSES rrrcn.

Parana MARCELLUS L. OLARKSON, OF OLAR'KSBURG, INDIANA.

PLUMB-BOB.

SPECIFICATION forming part of Letters Patent No. 310,122, dated December 30, 1884.

Application filed July 12, 1884.

(X0 model.)

dent of Olarksburg, in the county of Decatur and'State of Indiana, have invented certain new and useful Improvements in Plumb-Bobs; and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the aceompanyin g drawings, which form a part of this specification, and in which Figure l is a perspective view of my improved plumb-bob. Fig. 2 is a vertical sectional view of the same. Fig. 3 is a horizontal sectional view taken on the line a; x in Fig. 2, and Fig. i isahorizontal sectional view' taken on the line y y in Fig. 2.

The same letters refer to the same parts in all the figures.

This invention has relation to an improved plumb-bob for the use of carpenters and builders and for other purposes to which this class of devices are usually applied; and it has for its object to provide a device which may be used with equal eiiiciency and accuracy in all kinds of weather.

To this end it consists in the improved construction and arrangement of parts,which will be hereinafter fully described,and particularly pointed out in the claim.

In the drawings hereto annexed, A designates a casing, consisting of a back, B, sides 0 G, a top, D, and a supplementary or enlarged casing, D at its lower end. The casing D which may be constructed of sheet metal 01: other suitable material, is for the purpose of containing the weight or bob E, and it should be sufficiently wide to afford free play to the latter. The upper portion of the casing is provided with a front piece, F, which is at a sufficient distance from the back of said casing to allow the cord G, which supports the weight, to vibrate freely therein. The said cord is suitably attached to the roof or to a bracket, B near the upper end of the casing. The sides of the casing should be parallel to each other, and the front F is to be provided with an opening, II, which may be coveredwith glass or other transparent material. The back of the casing is to be provided in rear of the said opening with a block or plate, 0, embedded in the material of which the said back is made, and preferably of a contrasting color-as, for instance of light or white wood when the backing is of dark wood, and projecting some distance beyond the face of the said backing. This plate is provided on its face with a central vertical line, L", which is parallel to the sides of the casing.

The operation of this invention will be read ily understood when reference is had to the foregoing description, taken in connection with the drawings hereto annexed. It will be used practically in the same manner as in ordinary plumb-bobs, one of its vertical sides being applied to the wall which is to be plumbed, when the cord supporting the weight will indicate. by its position with relation to the vertical line or scale upon the face of the block or plate 0*, the angle which such wall occupies with relation to a horizontal plane. It is obvious that this principle may be ap plied to levels as well as to plumbs by simply attaching the casing which contains the weight to one of the arms of a straight-edge.

The advantages of this invention will be readily understood from the foregoing description. It is simple in construction, inexpensive, and not likely to get out of order, and its accuracy is never aifected or impaired by wind or rain, which often interferes seriously with the use of plumbs of the ordinary construction. It will also be seen that the block or plate 0 is nearly in contact with the cord G when the latter is plumb and while it vibrates, thus preventing the shadow thrown by In testimony that I claim the foregoing as my own I have hereunto affixed my signature 10 I in presence of two Witnesses.

MARCELLUS L. OLARKSON.

XVitnesses:

ARTHUR A. Cnnnownrn,

1 \VILLIAM E. HAT'roN. 

